Beijing Univ Technol, Coll Appl Sci, Inst Theoret Phys, Beijing 100022, Peoples R China
; Sichuan Univ, Dept Phys, Chengdu 610064, Peoples R China
; Chinese Acad Sci, Inst High Energy Phys, Beijing 100049, Peoples R China
; Chinese Acad Sci, Inst Theoret Phys, Beijing 100080, Peoples R China
The second order self-energies of hadrons are calculated from 2 matrix, and then an effective method to solve nuclear many-body problems is summarized. In addition, the density-dependent relativistic many body methods axe discussed.